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Changes of failure mechanism with increasing confinement, from extensional to shear-dominated failure, are widely observed in the rupture of intact specimens at the laboratory scale and in rock masses. In an analysis published in 2018, both unconfined and triaxial compressive tests were conducted to investigate the strength characteristics of 84 specimens of a Utah coal, including the spalling limits, the ratio of apparent unconfined compressive strength to unconfined compressive strength (UCS), the damage characteristics, and the post-yield dilatancy. These mechanical characteristics were found to be strongly anisotropic as a function of the orientation of the cleats relative to the loading direction, defined as the included angle. A total of four different included angles were used in the work performed in 2018. The authors found that the degree of anisotropic strength differed according to the included angle. However, the transition from extensional to shear failure at the given confinements was not clearly identified. In this study, a total of 20 specimens were additionally prepared from the same coal sample used in the previous study and then tested under both unconfined and triaxial compressive conditions. Because the authors already knew the most contrasting cases of the included angles from the previous work using the four included angles, they chose only two of the included angles (0° and 30°) for this study. For the triaxial compressive tests, a greater confining stress than the mean UCS was applied to the specimens in an attempt to identify the brittle-ductile transition of the coal. The new results have been compiled with the previous results in order to re-evaluate the confinement-dependency of the coal behavior. Additionally, the different confining stresses are used as analogs for different width-to-height ( W / H ) conditions of pillar strength. Although the W / H ratios of the specimens were not directly considered during testing, the equivalent W / H ratios of a pillar as a function of the confining stresses were estimated using an existing empirical solution. According to this relationship, the W / H at which in situ pillar behavior would be expected to transition from brittle to ductile is identified.

Plastic pollution is becoming a significant problem in urban areas due to excessive use and careless disposal. While studies on microplastics are increasingly being conducted across various environments, research on microplastics in soil is limited compared to other areas. Microplastics entering the soil through various routes can stay there for a long period of time, threatening soil organisms and eventually humans. Therefore, this study was carried out to investigate the distribution characteristics of microplastics according to types of land use. For this purpose, a total of 54 soil samples were collected from agricultural land, residential areas, roadsides, parks, and forests. The analysis of microplastics in the soil by stereo microscopy showed that the average numbers of microplastics (particles/kg) in agricultural land, residential areas, roadsides, parks, and forests were 5047, 3646, 4987, 2673, and 1097, respectively. Various colors (black, red, green, blue, yellow, white, and transparent) and shapes (fragment, fiber, film, and sphere) of microplastics were found in soils. The combination of black x fragment plastics showed the highest frequency. Microplastics in soil samples from agricultural land, roadside, and residential areas with sizes between 20 µm and 500 µm were determined using Fourier transform infrared spectrometer (FT-IR) and analyzed by MP finder. The number of microplastics detected in the soil with sizes ranging between 20 µm and 500 µm was in the order of roadside > residential areas > agricultural land, which was different from the results by stereomicroscopy. Polyethylene (PE), polypropylene (PP), and polymethyl methacrylate (PMMA) were detected in soils from roadsides. Polyurethane (PU), cellulose acetate (CA), polyethylene terephthalate (PET), PP, and polystyrene (PS) were detected in soils from residential areas, with PU being the most frequently detected.

INTRODUCTION We investigated longitudinal cognitive trajectories in relation to cerebrospinal fluid (CSF) proteomics in Alzheimer's disease (AD). METHODS Differential protein abundance analysis of proteomics (SomaScan 7K) data was performed for composite scores for domain‐specific cognitive functions (memory [MEM], executive function [EF], and language [LAN]) and their longitudinal changes in AD. This was followed by co‐abundance network analysis, functional enrichment analysis, and machine learning to identify co‐abundant protein modules, associated biological pathways, and prediction models of cognitive trajectories. RESULTS We identified proteins and pathways associated with composite scores for domain‐specific cognitive functions and their longitudinal changes. Proteins related to MEM and EF were primarily enriched in microglia and oligodendrocytes, respectively. The prediction model for the trajectories of cognitive decline achieved an area under the curve of up to 0.79. DISCUSSION Our findings suggest protein signatures and their functional pathways associated with longitudinal changes for cognitive decline, providing molecular insights into longitudinal cognitive trajectories in AD. Highlights Altered cerebrospinal fluid (CSF) protein levels were associated with cognitive functions at baseline. Altered CSF protein levels were associated with changes of cognitive decline. Proteins associated with memory were primarily enriched in microglia. Proteins associated with executive function were enriched in oligodendrocytes. The prediction performance for cognitive trajectories was improved up to 30.9%.

HighlightsDopant-tunable transparent conductive oxide (≤ 50 nm) fabricated via electric-field-driven metal implantation (m-TCOs; m= Ni, Ag, and Cu) is demonstrated.The m-TCOs exhibit ultrahigh transparency, low sheet resistance, and broad work function tunability, leading to outstanding performance in various optoelectronic devices.The work function change is attributed to the interstitial metal atoms that provide the empty d-orbital, resulting in the shift of the Fermi level.Ultrathin film-based transparent conductive oxides (TCOs) with a broad work function (WF) tunability are highly demanded for efficient energy conversion devices. However, reducing the film thickness below 50 nm is limited due to rapidly increasing resistance; furthermore, introducing dopants into TCOs such as indium tin oxide (ITO) to reduce the resistance decreases the transparency due to a trade-off between the two quantities. Herein, we demonstrate dopant-tunable ultrathin (≤ 50 nm) TCOs fabricated via electric field-driven metal implantation (m-TCOs; m = Ni, Ag, and Cu) without compromising their innate electrical and optical properties. The m-TCOs exhibit a broad WF variation (0.97 eV), high transmittance in the UV to visible range (89–93% at 365 nm), and low sheet resistance (30–60 Ω cm−2). Experimental and theoretical analyses show that interstitial metal atoms mainly affect the change in the WF without substantial losses in optical transparency. The m-ITOs are employed as anode or cathode electrodes for organic light-emitting diodes (LEDs), inorganic UV LEDs, and organic photovoltaics for their universal use, leading to outstanding performances, even without hole injection layer for OLED through the WF-tailored Ni-ITO. These results verify the proposed m-TCOs enable effective carrier transport and light extraction beyond the limits of traditional TCOs.

Genome-wide association studies (GWAS) on Alzheimer’s disease (AD) have predominantly focused on identifying common variants in Europeans. Here, we performed whole-genome sequencing (WGS) of 1,559 individuals from a Korean AD cohort to identify various genetic variants and biomarkers associated with AD. Our GWAS analysis identified a previously unreported locus for common variants ( APCDD1 ) associated with AD. Our WGS analysis was extended to explore the less-characterized genetic factors contributing to AD risk. We identified rare noncoding variants located in cis-regulatory elements specific to excitatory neurons associated with cognitive impairment. Moreover, structural variation analysis showed that short tandem repeat expansion was associated with an increased risk of AD, and copy number variant at the HPSE2 locus showed borderline statistical significance. APOE ε4 carriers with high polygenic burden or structural variants exhibited severe cognitive impairment and increased amyloid beta levels, suggesting a cumulative effects model of AD risk. Here the authors reveal via whole genome sequencing of an East Asian AD cohort a common variant locus (APCDD1), rare noncoding variants in excitatory neurons, and short tandem repeat expansions, suggesting a cumulative effects model for Alzheimer’s risk.

This study aimed to elaborate upon prior findings suggestive of the altered lateralization of structural connectivity in the developing preterm brain by using diffusion tensor imaging tractography to explore how network topological asymmetries in fronto-limbic neural circuitry are altered at 36–41 weeks, postmenstrual age in 64 preterm infants without severe brain injury and 33 term-born infants. We compared the pattern of structural connectivity and network lateralization of the betweenness centrality in the medial fronto-orbital gyrus, superior temporal gyrus, amygdala, and hippocampus—the structures comprising the fronto-limbic brain circuit—between preterm and term infants. Global efficiency, local efficiency, and small-world characteristics did not differ significantly between the two hemispheres in term-born infants, suggesting that integration and segregation are balanced between the left and right hemispheres. However, the preterm brain showed significantly greater leftward lateralization of small-worldness ( P  = 0.033); the lateralization index of the betweenness centrality revealed that the medial fronto-orbital gyrus ( P  = 0.008), superior temporal gyrus ( P  = 0.031), and hippocampus ( P  = 0.028) showed significantly increased leftward asymmetry in preterm infants relative to term-infants independent of sex, age at imaging, and bronchopulmonary dysplasia. The altered lateralization of fronto-limbic brain circuitry might be involved in the early development of social–emotional disorders in preterm infants.

GWAS of Alzheimer’s disease have been predominantly based on European ancestry cohorts with clinically diagnosed patients. Increasing the ancestral diversity of GWAS and focusing on imaging brain biomarkers for Alzheimer’s disease may lead to the identification of new genetic loci. Here, we perform a GWAS on cerebral β-amyloid deposition measured by PET imaging in 3,885 East Asians and a cross-ancestry GWAS meta-analysis with data from 11,816 European participants. Our GWAS analysis replicates known loci ( APOE4 , CR1 , and FERMT2 ) and identifies a novel locus near SORL1 that is significantly associated with β-amyloid deposition. Single-nucleus expression analysis shows that SORL1 is differentially expressed according to β-amyloid positivity in microglia. Our joint association analysis using the SORL1 lead variant (rs76490923) and the APOE4 allele demonstrates that the risk of β-amyloid deposition is reduced by up to 43.5% in APOE4 non-carriers and up to 55.6% in APOE4 carriers, according to the allelic dosage of the rs76490923 T allele. Our findings suggest that SORL1 may play an important role in the pathogenesis of Alzheimer’s disease, particularly in relation to β-amyloid deposition. A cross-ancestry GWAS meta-analysis of β-amyloid deposition in East Asian and European populations identifies a novel SORL1 locus and highlights its differential expression in microglia associated with β-amyloid positivity.

Alzheimer’s disease (AD) is characterized by amyloid-beta (Aβ) and tau pathologies that drive neuroinflammation and neurodegeneration. Free water (FW), a diffusion tensor imaging (DTI) metric reflecting extracellular fluid changes, has emerged as a sensitive marker of neuroinflammation. This study examined the role of FW in AD and its associations with plasma biomarkers, brain structural measures, and cognitive decline. We analyzed 968 participants across the AD continuum from Samsung Medical Center. Plasma biomarkers were measured using Single Molecule Array technology. DTI metrics (FW, fractional anisotropy (FA), and mean diffusivity (MD)) and structural MRI-derived hippocampal volume and cortical thickness were assessed. Plasma phosphorylated tau 217 (pTau217) significantly correlated with FW in both white matter (WM) and gray matter (GM), but not with FA or MD. All DTI metrics were associated with reduced hippocampal volume and lower cortical thickness. Mediation analyses revealed that FW in WM and GM had both direct and indirect associations with cognitive decline, while FA and MD were indirectly linked to cognitive outcomes through structural measures. These findings support FW as a sensitive marker of neuroinflammation, linking microstructural changes to macrostructural changes and cognitive outcomes. Integrating plasma biomarkers, DTI, and MRI may improve understanding of AD pathophysiology and support the development of targeted diagnostic and therapeutic approaches.

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by cerebral cortex atrophy. In this study, we used sparse canonical correlation analysis (SCCA) to identify associations between single nucleotide polymorphisms (SNPs) and cortical thickness in the Korean population. We also investigated the role of the SNPs in neurological outcomes, including neurodegeneration and cognitive dysfunction. We recruited 1125 Korean participants who underwent neuropsychological testing, brain magnetic resonance imaging, positron emission tomography, and microarray genotyping. We performed group-wise SCCA in Aβ negative (-) and Aβ positive (+) groups. In addition, we performed mediation, expression quantitative trait loci, and pathway analyses to determine the functional role of the SNPs. We identified SNPs related to cortical thickness using SCCA in Aβ negative and positive groups and identified SNPs that improve the prediction performance of cognitive impairments. Among them, rs9270580 was associated with cortical thickness by mediating Aβ uptake, and three SNPs (rs2271920, rs6859, rs9270580) were associated with the regulation of , , and genes. Our findings suggest that SNPs potentially contribute to cortical thickness in AD, which in turn leads to worse clinical outcomes. Our findings contribute to the understanding of the genetic architecture underlying cortical atrophy and its relationship with AD.

The charge excitation and decay pathways of two-dimensional heteroatomic quantum dots (QDs) are affected by the quantum confinement effect, bandgap structure and strong exciton binding energy. Recently, semiconducting transition metal dichalcogenides (TMDs) have been intensively studied; however, the charge dynamics of metallic phase QDs (mQDs) of TMDs remain relatively unknown. Herein, we investigate the photophysical properties of TMD-mQDs of two sizes, where the TMD-mQDs show different charge excitation and decay pathways that are mainly ascribed to the defect states and valence band splitting, resulting in a large Stokes shift and two excitation bands for maximum photoluminescence (PL). Interestingly, the dominant excitation band redshifts as the size increases, and the time-resolved PL peak redshifts at an excitation wavelength of 266 nm in the smaller QDs. Additionally, the lifetime is shortened in the larger QDs. From the structural and theoretical analysis, we discuss that the charge decay pathway in the smaller QDs is predominantly affected by edge oxidation, whereas the vacancies play an important role in the larger QDs.Metallic phase transition metal dichalcogenides quantum dots show different pathways of optical charge excitation and decay according to the size and sort of defects, resulting into the large Stoke shift, two bands for charge excitation, and TRPL peak shift. This result is mainly ascribed to the valance band splitting and the emerging defect states originated from atomic vacancy of basal plane and edge oxidation.